Tizen Window System by Gwan-gyeong Mun

1. Tizen Window System
2016-01-23 Tizen Talks
Gwan-gyeong Mun
Software R&D Center
Samsung Electronics

2. Copyright © 2016 Samsung Electronics, Co., Ltd. All rights reserved. 2
AppFramework / UI Framework / WindowSystem
Window System
Display Server + Window Manager + Etc ( Buffer
Management , GL Driver …)
Provide Visibility Feature for App Framework’s Life Cyle
Provide Window Resource ( with various WM policy )
for UI Framework

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AppCore with Window Manager
P
P
Window Manager
Send Visibility Event
for Resume State
Feat. 정우현

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EFL with Display Server
Window

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Window Manager Policy
Window Manager
controlls Window
Focus, Size, Stack,
etc…

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EFL / Window System in Tizen
Legend
Applications EFL & fontsWindow System
H/W
Linux Kernel Frame Buffer Input Devices
H/W
fontconfigfreetype2 OpenGL ES/EGL
Eet
Evas
Ecore
Eina
Edje
Elementary
Applications
X / Wayland Window System
Input
Service
Framework
&
Voice
Framework
kernel / Frame Buffer/ Input Devices
Graphics
ISF& Voice FW
Cairo

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Android? Tizen?
출처: https://source.android.com/devices/graphics/index.html
Enlightenment
Main Screen Mgr.
wm-
policy
Keyrouter
Comp
Window Effect
Composition
Enlightenment Foundation Library (EFL)
Ecore Evas
Xlib OpenGL ES / EGL
X Server / DRM TBM
Application

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Tizen Window System
Window Systems
X Window System
X Server + Enlightenment (Window Manager, E17)
~ Tizen 2.4
Wayland
Enlightenment ( Wayland Display Server, E19)
Tizen 3.0 ~

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Display Server / Window Manager (1)
Display Server
Control Input / Output
Window Manager
Window Policy
Window Size, Position, Stack, Visibility, Rotation
Window Compositing
Window Effect, NoComp Feature (HWC)
Etc
KeyRouter, Quickpanel Manager, ANR …

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Display Server / Window Manager (2)
X ( ~Tizen 2.4 )
Display Server : X Server
Window Manager: Enlightenment E17, works as X Client.
Wayland (Tizen 3.0 ~)
Display Server + Window Manager = Enlightenment E19

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Tizen Graphics Library(EFL) Backend
EFL(Enlightenment Foundation Library)
Backend ( X11, Wayland, DRM, Etc… )
Ecore
Event loop library with convenience modules
Ecore_X11, Ecore_Wayland, Ecore_Drm
Ecore_Evas
Glue to the backends
Ecore_Evas_X11, Ecore_Evas_Wayland,
Ecore_Evas_Drm
Evas
Canvas & rendering library
Evas_X11_Shm, Evas_X11_GL, Evas_Wayland_Shm,
Evas_Wayland_Egl, Evas_Drm, Evas_GL_Drm

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X Window System (~Tizen 2.4)
X Software Architecture
X has the client-server model architecture.
X logically be thought to be two part, the client linked
with Xlib called X client and the server which is
generally called X server.
X client
Xlib
X server
Network
requests
replies
events
Legend
X client
Xlib
X Server
X protocol

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X Software Architecture (~Tizen 2.4)
Application
Xlib
Window
Manager
Xlib
Application
Xlib
Toolkit
X server
Network
Device Drivers
Window Manager
A program written with Xlib.
It controls the placement and appearance of
application windows.
X window system
protocol requests are
sent from clients.
Events and replies are
passed back to clients.
Toolkit
Implements a set of user
interface features such as
menus or command
buttons.
Ex. EFL
Display Server
A program that runs on each
system that supports a display.
Display
A workstation consisting
of keyboard(s), pointing
devices, and one or
more screens.
Xlib
Provides functions for
connecting to a display
server, creating windows,
drawing graphics,
responding to events,
and so on.
Legend
X client
Xlib
Toolkit
X Server
Device drivers X protocol
requests replies
• X Software Architecture in detail

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X Window Manager (~Tizen 2.4)
X Window Manager
Window System 내의 모든 Window 들의 크기, 위치,
Stack 을 관리하는 특별한 X application
X Window Manager 종류: Enlightenment, Compiz,
Metacity, KWin, Mutter
Enlightenment
Enlightenment Foundation Library (EFL) 을 이용한 X
Window Manager.
Window management, Window composition, H/W
Key event 관리
Tizen Window Manager

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Tizen Window Manager (Compositing)
Window Composition
Window Composition 작업을 통해 Screen 출력
Window 상태 변경에 따라 Effect 수행
~ Tizen 2.4 : E17’s module , e-comp-tizen module
Tizen 3.0 ~ : E19, Compositor merged into
Enlightenment Core

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Compositing
1
2
3
SCREEN
(Phone/TV)
E17
COMP
X
SERVER
E19 Wayland Server
1
2
3

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Tizen Window Manager (Policy)
Window Layout Policy
App Window들의 크기, 위치, 스택을 결정 / 관리
Main Screen Manager: Desktop window layout policy
적용
Policy Module: Main Screen Manager 에서 적용한
window layout을 Tizen UX 에 적합한 형태로 전환
H/W Key event Delivery Policy
Keyrouter module
여러 H/W key (Volume, Home, Power button) event
관리

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Policy
1
2
3
SCREEN
(Phone/TV)
E17
Policy
X
SERVER
E19 Wayland Server
3
2
1
Stack / Size / Position 변경

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Visibility
1
2
E17
Policy
X
SERVER
E19 Wayland Server
SCREEN
(Phone/TV)
1
2
[Visibility State ]
1: Obscured
2: Unobscured
[Window 2 Create / Show]
1
2
E17
Policy
X
SERVER
E19 Wayland Server
[Visibility State ]
1: Unobscured
2: Obscured
[Window 1 Raise up]
1

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Window Manager Flow ( ~Tizen 2.4)
GPU Device DriverInput Device Driver
Application A
Enlightenment (E17)
Kernel
Legend & Acronym
Application
Enlightenment
Plug-in Module
Process
Plug-in
X Server
policy
X Video Driver
Application B
comp
X Input Driver
keyrouterDrawing
Window
Creation
Key Input
Drawing Flow
Window Creation Flow
Key Input Flow

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Window Manager Flow (Tizen 3.0)
GPU Device DriverInput Device Driver
Application A
Enlightenment (E19)
Kernel
policy
Application B
comp
keyrouterDrawing Window
Creation
Key Input
Legend & Acronym
Application
Enlightenment
Plug-in Module
Process
Plug-in
Drawing Flow
Window Creation Flow
Key Input Flow

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Wayland on Tizen 3.0
X Server
Composite
Window Mng.
Tizen App.
Xlib
Tizen App.
Xlib
Wayland
Compositor
Tizen App.
libwayland
Tizen App.
libwayland

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Wayland?
New-generation Display Server replacement for X Display Server.
Wayland is NOT the Display Server by itself.
it’s just a protocol which can communicate with Compositor and
Clients.
Doesn’t have rendering API.
There is NO additional functionality.
Slogan
“Every frame is perfect, by which I mean that applications will be able to
control the rendering enough that we’ll never see tearing, lag, redrawing
or flicker.”
- by Kristian Høgsberg -

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Why Wayland?
Core is extremely simple and small.
Give more work on Clients.
Smooth resize of the application window by optimized client-side
direct rendering and buffer control
Designed to be extendable and avoid round-trips
Easy to extend protocol for mobile, TV and wearable devices
Does not expose any direct client-to-client communication.
except passing file descriptors for selection and D&D data.

25. Reasons For Moving To Wayland
X Wayland
Rendering Support for H/W
Overlay by WM
No Yes
Support for Drawing
API
Yes No
Input Resource Limitation 255 Keycodes in theory, 232-1
Support for Server-
side Input Transform
No Yes
Security Protocol Code Hand written binary protocol parsing
code
Generated by
wayland-scanner
Input Event Different clients can receive events on
the same window and add other events.
Server sends
corresponding
events to a client.
Extensibility Ease of Porting Hard to adapt Relatively easy
Extension of protocol Hard to add while minimizing impact to
existing system functions (DIX, DDX)
Relatively easy
Event
System
Race condition Client – Server – WM Client – Server (WM)

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Display Buffer Management
Application에 제공되는 Buffer의 생성 주체
X
윈도우 버퍼 생성은 X Server가 처리
GL의 경우도 GL Driver 내부에서 X 서버에 요청하여
메모리 생성 (정확히는 X Video Driver에서 처리 )
Wayland
Window 에 사용되는 Buffer생성 주체는 클라이언트
GL의 경우에도 Client Side GL Driver가 버퍼 할당

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The Stack of Enlightenment Display Server
Application
X Server (Replaceable)
Operating System
EFL Library
E17 (WM)

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The Stack of Enlightenment Display Server
Application
(Wayland)
Enlightenment 0.19 (Compositor)
EFL Library
Operating System
Application
X Server (Replaceable)
Operating System
EFL Library
E17 (WM)

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Repos & Contact
Window System Repos on Tizen 3.0
https://review.tizen.org/git/platform/upstream/enlightenment
https://review.tizen.org/git/platform/core/uifw/e-mod-tizen-wm-policy
https://review.tizen.org/git/platform/upstream/efl
kk.moon@samsung.com

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Thank you